Editorial Type:
Picture of the month (MWR only)
Article Type:
Research Article

An Unusual Aerial Photograph of an Eddy Circulation in Marine Stratocumulus Clouds

Bradley M. Muller Department of Applied Aviation Sciences, Embry–Riddle Aeronautical University, Daytona Beach, Florida

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Christopher G. Herbster Department of Applied Aviation Sciences, Embry–Riddle Aeronautical University, Daytona Beach, Florida

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Frederick R. Mosher Department of Applied Aviation Sciences, Embry–Riddle Aeronautical University, Daytona Beach, Florida

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Print Publication:
01 Feb 2015
Collections:
Pictures of the Month in Monthly Weather Review
DOI:
https://doi.org/10.1175/MWR-D-13-00316.1
Page(s):
419–432
Restricted access

Abstract

An aerial photograph of a cyclonic, von Kármán–like vortex in the marine stratocumulus clouds off the California coast, taken by a commercial pilot near Grover Beach, is presented. It is believed that this is the first photograph of such an eddy, taken from an airplane, to appear in publication.

The eddy occurred with a strong inversion above a shallow marine boundary layer, in the lee of high, inversion-penetrating terrain. Tower and surface wind measurements plotted on satellite imagery demonstrate that the Grover Beach eddy was not just a cloud-level feature, but extended through the marine atmospheric boundary layer (MABL) to the surface. Evolution of the flow during the formation of the eddy appears similar to idealized numerical simulations of blocked MABL flow from the literature. The tower measurements sampled the northern part of the eddy circulation during its formation just offshore. The 2°–3°C temperature increases and then decreases during and after the eddy passage may be indicative of warmer air, from sheltered locations to the southeast, and/or downslope flow, being advected by and included into the eddy circulation. Satellite data compared with sequences of wind reversals at two different levels of the meteorological tower suggest that the eddy is tilted with height, at least during its formation stage. Formation mechanisms are discussed, but the subsynoptic observations are inadequate to resolve basic questions about the flow; ultimately a high-resolution model simulation is needed.

Denotes Open Access content.

Corresponding author address: Dr. Bradley M. Muller, Dept. of Applied Aviation Sciences, Embry-Riddle Aeronautical University, 600 S. Clyde Morris Blvd., Daytona Beach, FL 32114-3900. E-mail: mullerb@erau.edu

Abstract

An aerial photograph of a cyclonic, von Kármán–like vortex in the marine stratocumulus clouds off the California coast, taken by a commercial pilot near Grover Beach, is presented. It is believed that this is the first photograph of such an eddy, taken from an airplane, to appear in publication.

The eddy occurred with a strong inversion above a shallow marine boundary layer, in the lee of high, inversion-penetrating terrain. Tower and surface wind measurements plotted on satellite imagery demonstrate that the Grover Beach eddy was not just a cloud-level feature, but extended through the marine atmospheric boundary layer (MABL) to the surface. Evolution of the flow during the formation of the eddy appears similar to idealized numerical simulations of blocked MABL flow from the literature. The tower measurements sampled the northern part of the eddy circulation during its formation just offshore. The 2°–3°C temperature increases and then decreases during and after the eddy passage may be indicative of warmer air, from sheltered locations to the southeast, and/or downslope flow, being advected by and included into the eddy circulation. Satellite data compared with sequences of wind reversals at two different levels of the meteorological tower suggest that the eddy is tilted with height, at least during its formation stage. Formation mechanisms are discussed, but the subsynoptic observations are inadequate to resolve basic questions about the flow; ultimately a high-resolution model simulation is needed.

Denotes Open Access content.

Corresponding author address: Dr. Bradley M. Muller, Dept. of Applied Aviation Sciences, Embry-Riddle Aeronautical University, 600 S. Clyde Morris Blvd., Daytona Beach, FL 32114-3900. E-mail: mullerb@erau.edu
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  • Alpert, T., M. Tzidulko, and D. Iziksohn, 1999: A shallow, short-lived meso-β cyclone over the Gulf of Antalya, eastern Mediterranean. Tellus, 51A, 249–262, doi:10.1034/j.1600-0870.1999.t01-2-00006.x.

    • Search Google Scholar
    • Export Citation

  • Archer, C. L., and M. Z. Jacobson, 2005: The Santa Cruz Eddy. Part II: Mechanisms of formation. Mon. Wea. Rev., 133, 2387–2405, doi:10.1175/MWR2979.1.

    • Search Google Scholar
    • Export Citation

  • Archer, C. L., M. Z. Jacobson, and F. L. Ludwig, 2005: The Santa Cruz Eddy. Part I: Observations and statistics. Mon. Wea. Rev., 133, 767–782, doi:10.1175/MWR2885.1.

    • Search Google Scholar
    • Export Citation

  • Bosart, L. F., 1983: Analysis of a California Catalina eddy event. Mon. Wea. Rev., 111, 1619–1633, doi:10.1175/1520-0493(1983)111<1619:AOACCE>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Burk, S. D., and W. T. Thompson, 2004: Mesoscale eddy formation and shock features associated with a coastally trapped disturbance. Mon. Wea. Rev., 132, 2204–2223, doi:10.1175/1520-0493(2004)132<2204:MEFASF>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Chopra, K. P., and L. F. Hubert, 1965: Mesoscale eddies in wakes of islands. J. Atmos. Sci., 22, 652–657, doi:10.1175/1520-0469(1965)022<0652:MEIWOI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Dorman, C. E., and C. D. Winant, 2000: The structure and variability of the marine atmosphere around the Santa Barbara channel. Mon. Wea. Rev., 128, 261–282, doi:10.1175/1520-0493(2000)128<0261:TSAVOT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Dorman, C. E., and D. Koračin, 2008: Response of the summer marine layer flow to an extreme California coastal bend. Mon. Wea. Rev., 136, 2894–2992, doi:10.1175/2007MWR2336.1.

    • Search Google Scholar
    • Export Citation

  • Douglas, S. G., and R. C. Kessler, 1991: Analysis of mesoscale airflow patterns in the south-central coast air basin during the SCCCAMP 1985 intensive measurement periods. J. Appl. Meteor., 30, 607–631, doi:10.1175/1520-0450(1991)030<0607:AOMAPI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Eddington, L. W., J. J. O’Brien, and D. W. Stuart, 1992: Numerical simulation of topographically forced mesoscale variability in a well-mixed marine layer. Mon. Wea. Rev., 120, 2881–2896, doi:10.1175/1520-0493(1992)120<2881:NSOTFM>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Epifanio, C. C., and D. R. Durran, 2002a: Lee-vortex formation in free-slip stratified flow over ridges. Part I: Comparison of weakly nonlinear inviscid theory and fully nonlinear viscous simulations. J. Atmos. Sci., 59, 1153–1165, doi:10.1175/1520-0469(2002)059<1153:LVFIFS>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Epifanio, C. C., and D. R. Durran, 2002b: Lee-vortex formation in free-slip stratified flow over ridges. Part II: Mechanisms of vorticity and PV formation in nonlinear viscous wakes. J. Atmos. Sci., 59, 1166–1181, doi:10.1175/1520-0469(2002)059<1166:LVFIFS>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Epifanio, C. C., and R. Rotunno, 2005: The dynamics of orographic wake formation in flows with upstream blocking. J. Atmos. Sci., 62, 3127–3150, doi:10.1175/JAS3523.1.

    • Search Google Scholar
    • Export Citation

  • Etling, D., 1989: On atmospheric vortex streets in the wake of large islands. Meteor. Atmos. Phys., 41, 157–164, doi:10.1007/BF01043134.

    • Search Google Scholar
    • Export Citation

  • Haack, T., S. D. Burk, C. Dorman, and D. Rogers, 2001: Supercritical flow interaction within the Cape Blanco–Cape Mendocino orographic complex. Mon. Wea. Rev., 129, 688–708, doi:10.1175/1520-0493(2001)129<0688:SFIWTC>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Hanna, S. R., D. G. Strimaitus, J. S. Scire, G. E. Moore, and R. C. Kessler, 1991: Overview of results of analysis of data from the South-Central Coast Cooperative Aerometric Monitoring Program (SCCCAMP 1985). J. Appl. Meteor., 30, 511–533, doi:10.1175/1520-0450(1991)030<0511:OOROAO>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Heinze, R., S. Raasch, and D. Etling, 2012: The structure of Kármán vortex streets in the atmospheric boundary layer derived from large eddy simulation. Meteor. Z., 21, 221–237, doi:10.1127/0941-2948/2012/0313.

    • Search Google Scholar
    • Export Citation

  • Hubert, L. F., and A. F. Krueger, 1962: Satellite pictures of mesoscale eddies. Mon. Wea. Rev., 90, 457–463, doi:10.1175/1520-0493(1962)090<0457:SPOME>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Jiang, Q., and R. B. Smith, 2000: V-waves, bow shocks, and wakes in supercritical hydrostatic flow. J. Fluid Mech., 406, 27–53, doi:10.1017/S0022112099007636.

    • Search Google Scholar
    • Export Citation

  • Kessler, R. C., and S. G. Douglas, 1991: Numerical simulation of topographically forced mesoscale variability in a well-mixed marine layer. J. Appl. Meteor., 30, 633–651, doi:10.1175/1520-0450(1991)030<0633:ANSOME>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Lester, P. F., 1985: Studies of the marine inversion over the San Francisco Bay area…A summary of the work of Albert Miller, 1961–1978. Bull. Amer. Meteor. Soc., 66, 1396–1402, doi:10.1175/1520-0477(1985)066<1396:SOTMIO>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Li, X., P. Clemente-Colon, W. G. Pichel, and P. W. Vachon, 2000: Atmospheric vortex streets on a RADARSAT SAR image. Geophys. Res. Lett., 27, 1655–1658, doi:10.1029/1999GL011212.

    • Search Google Scholar
    • Export Citation

  • Lyons, W. A., and T. Fujita, 1968: Mesoscale motions in oceanic stratus as revealed by satellite data. Mon. Wea. Rev., 96, 304–314, doi:10.1175/1520-0493(1968)096<0304:MMIOSA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Mass, C. F., and M. D. Albright, 1989: Origin of the Catalina eddy. Mon. Wea. Rev., 117, 2406–2436, doi:10.1175/1520-0493(1989)117<2406:OOTCE>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Mosher, F. R., 2013: Attempting to turn night into day; development of visible like nighttime satellite images. 16th Conf. on Aviation, Range, and Aerospace Meteorology, Austin, TX, Amer. Meteor. Soc., 5.6. [Available online at https://ams.confex.com/ams/93Annual/webprogram/Paper210902.html.]

  • NCAR, 2014: NCAR Command Language, version 6.2.0. UCAR/NCAR/CISL/VETS, doi:10.5065/D6WD3XH5.

  • Orlanski, I., 1975: A rational subdivision of scales for atmospheric processes. Bull. Amer. Meteor. Soc., 56, 527–530.

  • Parish, T. R., D. A. Rahn, and D. Leon, 2013: Airborne observations of a Catalina eddy. Mon. Wea. Rev., 141, 3300–3313, doi:10.1175/MWR-D-13-00029.1.

    • Search Google Scholar
    • Export Citation

  • Porter, J. N., D. Stevens, K. Roe, S. Kono, D. Kress, and E. Lau, 2007: Wind environment in the lee of Kauai Island, Hawaii during trade wind conditions: Weather setting for the Helios mishap. Bound.-Layer Meteor., 123, 463–480, doi:10.1007/s10546-007-9155-z.

    • Search Google Scholar
    • Export Citation

  • Rahn, D. A., T. R. Parish, and D. Leon, 2013: Airborne measurements of coastal jet transition around Point Conception, California. Mon. Wea. Rev., 141, 3827–3839, doi:10.1175/MWR-D-13-00030.1.

    • Search Google Scholar
    • Export Citation

  • Rosenthal, J., 1968: A Catalina eddy. Mon. Wea. Rev., 96, 742–743, doi:10.1175/1520-0493(1968)096<0742:ACE>2.0.CO;2.

  • Ruscher, P. H., and J. W. Deardorff, 1982: A numerical simulation of an atmospheric vortex street. Tellus, 34A, 555–566, doi:10.1111/j.2153-3490.1982.tb01844.x.

    • Search Google Scholar
    • Export Citation

  • Schär, C., and R. B. Smith, 1993: Shallow-water flow past isolated topography. Part I: Vorticity production and wake formation. J. Atmos. Sci., 50, 1373–1400, doi:10.1175/1520-0469(1993)050<1373:SWFPIT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Schär, C., and D. R. Durran, 1997: Vortex formation and vortex shedding in continuously stratified flows past isolated topography. J. Atmos. Sci., 54, 534–554, doi:10.1175/1520-0469(1997)054<0534:VFAVSI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Smolarkiewicz, P. K., and R. Rotunno, 1989a: Low Froude number flow past three-dimensional obstacles. Part I: Baroclinically generated lee vortices. J. Atmos. Sci., 46, 1154–1164, doi:10.1175/1520-0469(1989)046<1154:LFNFPT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Smolarkiewicz, P. K., and R. Rotunno, 1989b: Reply. J. Atmos. Sci., 46, 3614–3617, doi:10.1175/1520-0469(1989)046<3614:R>2.0.CO;2.

  • Sun, W.-Y., and J.-D. Chern, 1994: Numerical experiments of vortices in the wakes of large idealized mountains. J. Atmos. Sci., 51, 191–209, doi:10.1175/1520-0469(1994)051<0191:NEOVIT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Thompson, W. T., S. D. Burk, and J. Rosenthal, 1997: An investigation of the Catalina eddy. Mon. Wea. Rev., 125, 1135–1146, doi:10.1175/1520-0493(1997)125<1135:AIOTCE>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Thomson, R. E., J. F. R. Gower, and N. W. Bowker, 1977: Vortex streets in the wake of the Aleutian Islands. Mon. Wea. Rev., 105, 873–884, doi:10.1175/1520-0493(1977)105<0873:VSITWO>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Thuillier, R. H., 1987: Real-time analysis of local wind patterns for application to nuclear-emergency response. Bull. Amer. Meteor. Soc., 68, 1111–1115, doi:10.1175/1520-0477(1987)068<1111:RTAOLW>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Wakimoto, R. M., 1987: The Catalina eddy and its effect on pollution over southern California. Mon. Wea. Rev., 115, 837–855, doi:10.1175/1520-0493(1987)115<0837:TCEAIE>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Wilczak, J. M., W. F. Dabberdt, and R. A. Kropfli, 1991: Observations and numerical-model simulations of the atmospheric boundary layer in the Santa Barbara coastal region. J. Appl. Meteor., 30, 652–673, doi:10.1175/1520-0450(1991)030<0652:OANMSO>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Young, G. S., and J. Zawislak, 2006: An observational study of vortex spacing in island wake vortex streets. Mon. Wea. Rev., 134, 2285–2294, doi:10.1175/MWR3186.1.

    • Search Google Scholar
    • Export Citation
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